1. Field of the Invention
The present invention relates to a device for cleaning the wiper blades of window wipers, such as vehicle windscreen or windshield wipers. The device has the form of a self-adhesive flat strip which is intended to be fastened to the outer surface of the vehicle windscreen in the region of the sweeping movement of the wiper blade.
2. Description of the Prior Art
When an automotive vehicle is driven on wet and muddy roads, particularly in the rain, dirt and grease of different kinds adhere to the windscreen wiper blades/headlamp wiper blades of the vehicle. In time, the initially smooth wiping surfaces of the wiper blades become uneven, thereby greatly impairing the wiping effect of the blades. Different devices for cleaning wiper blades from contaminants that adhere thereto and for restoring the wiping surfaces of such blades to their original smooth state are commercially available. These devices typically include a narrow gap which is located between two opposing scraper surfaces and which is intended to be placed manually over and drawn along a wiper blade with the intention of cleaning the blade. Cleaning devices of this kind, however, cannot be used while the vehicle is being driven, when the need is greatest. Attempts have been made to solve this problem by providing in the windscreen, immediately upstream of the lower turning position of a wiper blade, a sharp-edged recess over which the wiper blade is intended to sweep as it moves. One drawback with this solution, however, is that a newly fitted wiper blade will also pass over the cleaning device, resulting in premature wear of the wiper blade. The intention with a cleaning device of the kind meant here is for the device to begin to function only when the wiper blade begins to wear, i.e. after a new wiper blade has been used for some time. Accordingly, it has been proposed to attach to the windscreen a foil strip which while having the same function as the scraper fitted into the windscreen can be applied subsequently, when the wiper blade begins to wear. A foil strip of this kind is known from U.S. Pat. No. 4,685,168. Although this smooth cleaner strip is simple, it fails to provide the desired cleaning effect and because of its relatively large thickness results in rapid wear on the wiper blade. An attempt to solve the cleaning problem is described in U.S. Pat. No. 5,226,199, which teaches a windscreen mounted strip which is provided with a zig-zag pattern or a wart-like pattern with the hope that the cleaning effect will be improved in this way. The ridges formed by the warts or the zig-zag pattern have a rounded shape. Apart from the fact that the strip is relatively expensive in manufacture, it also fails to provide the desired cleaning effect. Other cleaning patterns are also known to the art. For instance, DE 3,138,388 teaches a foil strip which has an arched or curved profile shape and which includes longitudinally extending sharp-edged furrows. Because the furrows are formed in the strip, it is necessary for the strip to be relatively thick (seen in relation to the product concerned), and consequently it is necessary to profile the strip with the aforesaid arched or curved configuration. As a result, the strip is expensive in manufacture and does not provide a satisfactory cleaning effect.
One object of the present invention is to solve the problems associated with known cleaning devices, while another object of the invention is to provide a device which can be easily fitted to a windscreen with the intention of keeping the wiper blades clean. Both objects are achieved in accordance with the invention with a device having the characteristic features defined in the claims.